Find Perfect Numbers in C++

Posted by Samath
  1561
December 26, 2014

 

A positive integer is called a perfect number if it is equal to the sum of all of its positive divisors, excluding itself.  For example, 6 is the first perfect number because 6=3+2+1. The next is 28=14+7+4+2+1. There are four perfect numbers less than 10000. Write a program to find all these four numbers.

Code:

#include <iostream>
#include <cstdlib>
 
using namespace std;
 
int main(int argc, char *argv[])
{
	int num = 1;
    int sum,divisor;
        
    while(num<=10000)
	{
 		sum = 0; 
        divisor=1;  
 
        while(divisor<=num/2)
		{
  			if((num%divisor)==0)
            {                          
            	sum+=divisor;   
            }
 				divisor++;
 		 } 
 
         if(sum==num)
		 {
            cout<<"Perfect numbers less than 10000: "<<num<<"\n";
 		 }
 			num++;
   } 
	return 0;
}